The present invention relates generally to alarms, and in particular to a combination smoke and burglar alarm which is actuated both by the sensing of smoke and by the unauthorized opening of a door or window.
A wide variety of alarms and alarm systems are available for use in homes and businesses, and often the alarm systems are of the combined type wherein both fire and intrusion are detected. In one type of alarm system, magnetic switches, interrupted light beams or infrared detectors indicate an unauthorized intrusion and smoke or heat detectors detect the occurance of a fire. These remote detection devices then transmit signals to a central system which sounds an audible alarm and/or automatically dials the local police or fire department to report the intrusion or fire.
Individual, decentralized burglar alarms are also known, and these alarms are typically mounted at each door or window where intrusion is to be detected and are activated by the opening of the door or window to sound an audible alarm.
Smoke alarms are in widespread use throughout most homes, hotels, restaurants and businesses, and have even been mandated for use in certain establishments, such as hotels, by state legislation. Smoke alarms of this type are well known and generally comprise a housing which is mounted to a wall or ceiling, and contains the battery powered smoke detection circuitry which sounds a horn or the like when a certain level of smoke is detected. In order to enable the user to test the system to ensure that the battery has not run down and that the alarm would be capable of operating when smoke is detected, the smoke alarms are typically provided with a tester button that protrudes through an opening in the housing. The user can depress the tester button against the spring bias of the tester button to activate the circuitry thereby causing the audible alarm to sound. Such tester buttons are typically mounted on the face of the housing, but may also be side mounted.